The present invention relates to a novel synthetic resin composition or, more particularly, to a synthetic resin composition particularly suitable as a molding material of chassis for electric and electronic instruments having outstandingly high heat resistance, rigidity and dimensional stability as well as to a chassis molded from the resin composition.
As is known, many of chassis in electric and electronic instruments are shaped from a synthetic resin composition. Essential requirements for such a resin-made chassis include high heat resistance, flame retardancy, rigidity and dimensional stability. Currently, the resin compositions directed to this application are mainly composed of a polycarbonate resin, polysulfone resin and the like belonging to the class of so-called engineering plastics and glass fibers as a reinforcing material. These engineering plastics, however, are generally expensive so that the costs for the preparation of chassis from the resin composition are also unavoidably high not to be economical.
Accordingly, it is proposed to use a glass fiber-reinforced resin composition comprising a polystyrene resin modified with an acid anhydride monomer as a class of less expensive plastic resins (see, for example, Japanese Patent Publication 49-19097). Though somewhat improved in respect of the impact strength, such a resin composition has a problem that the shaped article such as chassis prepared therefrom sometimes suffers appearance of crazes because of the formation of microscopic interstices between the matrix phase of the resin and the surface of the glass fibers.